Convert 530 grams of Sodium carbonate (Na2CO3) into moles of Sodium carbonate (Na2CO3) Enter your answer(s) here
Convert 4.2 moles of H2O into grams of H2O
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How many moles are in 12.04 x 10^23 particles of O2 ?
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How many particles are in 3 moles of magnesium (Mg)?

1. 5 moles

2. 75.6 grams

3. 2 moles

4.  1.806 x 10²⁴ particles

Given

mass and moles of compound

Required

mass, moles and number of particles

Solution

1. 530 g Na2CO3

mol = 530 g : 106 g/mol

mol = 5

2. 4.2 moles H2O

mass = 4.2 moles x 18 g/mol

mass = 75.6 grams

3. 12.04 x 10²³ O2

mol =   12.04 x 10²³ : 6.02  x 10²³

mol = 2

4. 3 moles of Mg

particles = 3 x 6.02  x 10²³

particles = 1.806 x 10²⁴

supongo que te refieres al paralaje estelar (observable).

si es así, entonces se puede inferir que la estrella está a más de 200 parsecs.

linda: 3 ; laura: 15

step-by-step explanation:

note that linda + laura's age is 18, and that linda is 12 years younger than her sister.

let "linda" = x , "laura" = y:

x + y = 18

x = y - 12

first, plug in y - 12 for x in the first equation:

(y - 12) + y = 18

simplify.

2y - 12 = 18

isolate the variable (y). note the equal sign, what you do to one side, you do to the other. do the opposite of pemdas. first add, then divide.

2y - 12 (+12) = 18 (+12)

2y = 18 + 12

2y = 30

(2y)/2 = (30)/2

y = 30/2

y = 15

next, plug in 15 for y in the second equation (the other equation would work too).

x = y - 12

x = (15) - 12

x = 3

linda's age is 3, laura's age is 15.

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